1 | =head1 NAME
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2 |
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3 | perllocale - Perl locale handling (internationalization and localization)
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4 |
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5 | =head1 DESCRIPTION
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6 |
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7 | Perl supports language-specific notions of data such as "is this
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8 | a letter", "what is the uppercase equivalent of this letter", and
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9 | "which of these letters comes first". These are important issues,
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10 | especially for languages other than English--but also for English: it
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11 | would be naE<iuml>ve to imagine that C<A-Za-z> defines all the "letters"
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12 | needed to write in English. Perl is also aware that some character other
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13 | than '.' may be preferred as a decimal point, and that output date
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14 | representations may be language-specific. The process of making an
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15 | application take account of its users' preferences in such matters is
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16 | called B<internationalization> (often abbreviated as B<i18n>); telling
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17 | such an application about a particular set of preferences is known as
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18 | B<localization> (B<l10n>).
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19 |
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20 | Perl can understand language-specific data via the standardized (ISO C,
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21 | XPG4, POSIX 1.c) method called "the locale system". The locale system is
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22 | controlled per application using one pragma, one function call, and
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23 | several environment variables.
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24 |
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25 | B<NOTE>: This feature is new in Perl 5.004, and does not apply unless an
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26 | application specifically requests it--see L<Backward compatibility>.
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27 | The one exception is that write() now B<always> uses the current locale
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28 | - see L<"NOTES">.
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29 |
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30 | =head1 PREPARING TO USE LOCALES
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31 |
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32 | If Perl applications are to understand and present your data
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33 | correctly according a locale of your choice, B<all> of the following
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34 | must be true:
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35 |
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36 | =over 4
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37 |
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38 | =item *
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39 |
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40 | B<Your operating system must support the locale system>. If it does,
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41 | you should find that the setlocale() function is a documented part of
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42 | its C library.
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43 |
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44 | =item *
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45 |
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46 | B<Definitions for locales that you use must be installed>. You, or
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47 | your system administrator, must make sure that this is the case. The
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48 | available locales, the location in which they are kept, and the manner
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49 | in which they are installed all vary from system to system. Some systems
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50 | provide only a few, hard-wired locales and do not allow more to be
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51 | added. Others allow you to add "canned" locales provided by the system
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52 | supplier. Still others allow you or the system administrator to define
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53 | and add arbitrary locales. (You may have to ask your supplier to
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54 | provide canned locales that are not delivered with your operating
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55 | system.) Read your system documentation for further illumination.
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56 |
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57 | =item *
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58 |
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59 | B<Perl must believe that the locale system is supported>. If it does,
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60 | C<perl -V:d_setlocale> will say that the value for C<d_setlocale> is
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61 | C<define>.
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62 |
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63 | =back
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64 |
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65 | If you want a Perl application to process and present your data
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66 | according to a particular locale, the application code should include
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67 | the S<C<use locale>> pragma (see L<The use locale pragma>) where
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68 | appropriate, and B<at least one> of the following must be true:
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69 |
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70 | =over 4
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71 |
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72 | =item *
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73 |
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74 | B<The locale-determining environment variables (see L<"ENVIRONMENT">)
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75 | must be correctly set up> at the time the application is started, either
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76 | by yourself or by whoever set up your system account.
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77 |
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78 | =item *
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79 |
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80 | B<The application must set its own locale> using the method described in
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81 | L<The setlocale function>.
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82 |
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83 | =back
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84 |
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85 | =head1 USING LOCALES
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86 |
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87 | =head2 The use locale pragma
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88 |
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89 | By default, Perl ignores the current locale. The S<C<use locale>>
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90 | pragma tells Perl to use the current locale for some operations:
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91 |
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92 | =over 4
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93 |
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94 | =item *
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95 |
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96 | B<The comparison operators> (C<lt>, C<le>, C<cmp>, C<ge>, and C<gt>) and
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97 | the POSIX string collation functions strcoll() and strxfrm() use
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98 | C<LC_COLLATE>. sort() is also affected if used without an
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99 | explicit comparison function, because it uses C<cmp> by default.
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100 |
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101 | B<Note:> C<eq> and C<ne> are unaffected by locale: they always
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102 | perform a char-by-char comparison of their scalar operands. What's
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103 | more, if C<cmp> finds that its operands are equal according to the
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104 | collation sequence specified by the current locale, it goes on to
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105 | perform a char-by-char comparison, and only returns I<0> (equal) if the
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106 | operands are char-for-char identical. If you really want to know whether
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107 | two strings--which C<eq> and C<cmp> may consider different--are equal
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108 | as far as collation in the locale is concerned, see the discussion in
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109 | L<Category LC_COLLATE: Collation>.
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110 |
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111 | =item *
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112 |
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113 | B<Regular expressions and case-modification functions> (uc(), lc(),
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114 | ucfirst(), and lcfirst()) use C<LC_CTYPE>
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115 |
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116 | =item *
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117 |
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118 | B<The formatting functions> (printf(), sprintf() and write()) use
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119 | C<LC_NUMERIC>
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120 |
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121 | =item *
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122 |
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123 | B<The POSIX date formatting function> (strftime()) uses C<LC_TIME>.
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124 |
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125 | =back
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126 |
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127 | C<LC_COLLATE>, C<LC_CTYPE>, and so on, are discussed further in
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128 | L<LOCALE CATEGORIES>.
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129 |
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130 | The default behavior is restored with the S<C<no locale>> pragma, or
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131 | upon reaching the end of block enclosing C<use locale>.
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132 |
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133 | The string result of any operation that uses locale
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134 | information is tainted, as it is possible for a locale to be
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135 | untrustworthy. See L<"SECURITY">.
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136 |
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137 | =head2 The setlocale function
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138 |
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139 | You can switch locales as often as you wish at run time with the
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140 | POSIX::setlocale() function:
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141 |
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142 | # This functionality not usable prior to Perl 5.004
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143 | require 5.004;
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144 |
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145 | # Import locale-handling tool set from POSIX module.
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146 | # This example uses: setlocale -- the function call
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147 | # LC_CTYPE -- explained below
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148 | use POSIX qw(locale_h);
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149 |
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150 | # query and save the old locale
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151 | $old_locale = setlocale(LC_CTYPE);
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152 |
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153 | setlocale(LC_CTYPE, "fr_CA.ISO8859-1");
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154 | # LC_CTYPE now in locale "French, Canada, codeset ISO 8859-1"
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155 |
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156 | setlocale(LC_CTYPE, "");
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157 | # LC_CTYPE now reset to default defined by LC_ALL/LC_CTYPE/LANG
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158 | # environment variables. See below for documentation.
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159 |
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160 | # restore the old locale
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161 | setlocale(LC_CTYPE, $old_locale);
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162 |
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163 | The first argument of setlocale() gives the B<category>, the second the
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164 | B<locale>. The category tells in what aspect of data processing you
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165 | want to apply locale-specific rules. Category names are discussed in
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166 | L<LOCALE CATEGORIES> and L<"ENVIRONMENT">. The locale is the name of a
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167 | collection of customization information corresponding to a particular
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168 | combination of language, country or territory, and codeset. Read on for
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169 | hints on the naming of locales: not all systems name locales as in the
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170 | example.
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171 |
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172 | If no second argument is provided and the category is something else
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173 | than LC_ALL, the function returns a string naming the current locale
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174 | for the category. You can use this value as the second argument in a
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175 | subsequent call to setlocale().
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176 |
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177 | If no second argument is provided and the category is LC_ALL, the
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178 | result is implementation-dependent. It may be a string of
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179 | concatenated locales names (separator also implementation-dependent)
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180 | or a single locale name. Please consult your L<setlocale(3)> for
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181 | details.
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182 |
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183 | If a second argument is given and it corresponds to a valid locale,
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184 | the locale for the category is set to that value, and the function
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185 | returns the now-current locale value. You can then use this in yet
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186 | another call to setlocale(). (In some implementations, the return
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187 | value may sometimes differ from the value you gave as the second
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188 | argument--think of it as an alias for the value you gave.)
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189 |
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190 | As the example shows, if the second argument is an empty string, the
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191 | category's locale is returned to the default specified by the
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192 | corresponding environment variables. Generally, this results in a
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193 | return to the default that was in force when Perl started up: changes
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194 | to the environment made by the application after startup may or may not
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195 | be noticed, depending on your system's C library.
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196 |
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197 | If the second argument does not correspond to a valid locale, the locale
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198 | for the category is not changed, and the function returns I<undef>.
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199 |
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200 | For further information about the categories, consult L<setlocale(3)>.
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201 |
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202 | =head2 Finding locales
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203 |
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204 | For locales available in your system, consult also L<setlocale(3)> to
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205 | see whether it leads to the list of available locales (search for the
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206 | I<SEE ALSO> section). If that fails, try the following command lines:
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207 |
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208 | locale -a
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209 |
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210 | nlsinfo
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211 |
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212 | ls /usr/lib/nls/loc
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213 |
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214 | ls /usr/lib/locale
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215 |
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216 | ls /usr/lib/nls
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217 |
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218 | ls /usr/share/locale
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219 |
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220 | and see whether they list something resembling these
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221 |
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222 | en_US.ISO8859-1 de_DE.ISO8859-1 ru_RU.ISO8859-5
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223 | en_US.iso88591 de_DE.iso88591 ru_RU.iso88595
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224 | en_US de_DE ru_RU
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225 | en de ru
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226 | english german russian
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227 | english.iso88591 german.iso88591 russian.iso88595
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228 | english.roman8 russian.koi8r
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229 |
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230 | Sadly, even though the calling interface for setlocale() has been
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231 | standardized, names of locales and the directories where the
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232 | configuration resides have not been. The basic form of the name is
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233 | I<language_territory>B<.>I<codeset>, but the latter parts after
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234 | I<language> are not always present. The I<language> and I<country>
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235 | are usually from the standards B<ISO 3166> and B<ISO 639>, the
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236 | two-letter abbreviations for the countries and the languages of the
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237 | world, respectively. The I<codeset> part often mentions some B<ISO
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238 | 8859> character set, the Latin codesets. For example, C<ISO 8859-1>
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239 | is the so-called "Western European codeset" that can be used to encode
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240 | most Western European languages adequately. Again, there are several
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241 | ways to write even the name of that one standard. Lamentably.
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242 |
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243 | Two special locales are worth particular mention: "C" and "POSIX".
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244 | Currently these are effectively the same locale: the difference is
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245 | mainly that the first one is defined by the C standard, the second by
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246 | the POSIX standard. They define the B<default locale> in which
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247 | every program starts in the absence of locale information in its
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248 | environment. (The I<default> default locale, if you will.) Its language
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249 | is (American) English and its character codeset ASCII.
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250 |
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251 | B<NOTE>: Not all systems have the "POSIX" locale (not all systems are
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252 | POSIX-conformant), so use "C" when you need explicitly to specify this
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253 | default locale.
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254 |
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255 | =head2 LOCALE PROBLEMS
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256 |
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257 | You may encounter the following warning message at Perl startup:
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258 |
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259 | perl: warning: Setting locale failed.
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260 | perl: warning: Please check that your locale settings:
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261 | LC_ALL = "En_US",
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262 | LANG = (unset)
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263 | are supported and installed on your system.
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264 | perl: warning: Falling back to the standard locale ("C").
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265 |
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266 | This means that your locale settings had LC_ALL set to "En_US" and
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267 | LANG exists but has no value. Perl tried to believe you but could not.
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268 | Instead, Perl gave up and fell back to the "C" locale, the default locale
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269 | that is supposed to work no matter what. This usually means your locale
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270 | settings were wrong, they mention locales your system has never heard
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271 | of, or the locale installation in your system has problems (for example,
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272 | some system files are broken or missing). There are quick and temporary
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273 | fixes to these problems, as well as more thorough and lasting fixes.
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274 |
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275 | =head2 Temporarily fixing locale problems
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276 |
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277 | The two quickest fixes are either to render Perl silent about any
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278 | locale inconsistencies or to run Perl under the default locale "C".
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279 |
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280 | Perl's moaning about locale problems can be silenced by setting the
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281 | environment variable PERL_BADLANG to a zero value, for example "0".
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282 | This method really just sweeps the problem under the carpet: you tell
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283 | Perl to shut up even when Perl sees that something is wrong. Do not
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284 | be surprised if later something locale-dependent misbehaves.
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285 |
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286 | Perl can be run under the "C" locale by setting the environment
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287 | variable LC_ALL to "C". This method is perhaps a bit more civilized
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288 | than the PERL_BADLANG approach, but setting LC_ALL (or
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289 | other locale variables) may affect other programs as well, not just
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290 | Perl. In particular, external programs run from within Perl will see
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291 | these changes. If you make the new settings permanent (read on), all
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292 | programs you run see the changes. See L<ENVIRONMENT> for
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293 | the full list of relevant environment variables and L<USING LOCALES>
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294 | for their effects in Perl. Effects in other programs are
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295 | easily deducible. For example, the variable LC_COLLATE may well affect
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296 | your B<sort> program (or whatever the program that arranges "records"
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297 | alphabetically in your system is called).
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298 |
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299 | You can test out changing these variables temporarily, and if the
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300 | new settings seem to help, put those settings into your shell startup
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301 | files. Consult your local documentation for the exact details. For in
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302 | Bourne-like shells (B<sh>, B<ksh>, B<bash>, B<zsh>):
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303 |
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304 | LC_ALL=en_US.ISO8859-1
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305 | export LC_ALL
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306 |
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307 | This assumes that we saw the locale "en_US.ISO8859-1" using the commands
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308 | discussed above. We decided to try that instead of the above faulty
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309 | locale "En_US"--and in Cshish shells (B<csh>, B<tcsh>)
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310 |
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311 | setenv LC_ALL en_US.ISO8859-1
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312 |
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313 | or if you have the "env" application you can do in any shell
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314 |
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315 | env LC_ALL=en_US.ISO8859-1 perl ...
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316 |
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317 | If you do not know what shell you have, consult your local
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318 | helpdesk or the equivalent.
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319 |
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320 | =head2 Permanently fixing locale problems
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321 |
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322 | The slower but superior fixes are when you may be able to yourself
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323 | fix the misconfiguration of your own environment variables. The
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324 | mis(sing)configuration of the whole system's locales usually requires
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325 | the help of your friendly system administrator.
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326 |
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327 | First, see earlier in this document about L<Finding locales>. That tells
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328 | how to find which locales are really supported--and more importantly,
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329 | installed--on your system. In our example error message, environment
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330 | variables affecting the locale are listed in the order of decreasing
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331 | importance (and unset variables do not matter). Therefore, having
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332 | LC_ALL set to "En_US" must have been the bad choice, as shown by the
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333 | error message. First try fixing locale settings listed first.
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334 |
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335 | Second, if using the listed commands you see something B<exactly>
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336 | (prefix matches do not count and case usually counts) like "En_US"
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337 | without the quotes, then you should be okay because you are using a
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338 | locale name that should be installed and available in your system.
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339 | In this case, see L<Permanently fixing your system's locale configuration>.
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340 |
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341 | =head2 Permanently fixing your system's locale configuration
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342 |
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343 | This is when you see something like:
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344 |
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345 | perl: warning: Please check that your locale settings:
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346 | LC_ALL = "En_US",
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347 | LANG = (unset)
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348 | are supported and installed on your system.
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349 |
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350 | but then cannot see that "En_US" listed by the above-mentioned
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351 | commands. You may see things like "en_US.ISO8859-1", but that isn't
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352 | the same. In this case, try running under a locale
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353 | that you can list and which somehow matches what you tried. The
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354 | rules for matching locale names are a bit vague because
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355 | standardization is weak in this area. See again the
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356 | L<Finding locales> about general rules.
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357 |
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358 | =head2 Fixing system locale configuration
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359 |
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360 | Contact a system administrator (preferably your own) and report the exact
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361 | error message you get, and ask them to read this same documentation you
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362 | are now reading. They should be able to check whether there is something
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363 | wrong with the locale configuration of the system. The L<Finding locales>
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364 | section is unfortunately a bit vague about the exact commands and places
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365 | because these things are not that standardized.
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366 |
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367 | =head2 The localeconv function
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368 |
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369 | The POSIX::localeconv() function allows you to get particulars of the
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370 | locale-dependent numeric formatting information specified by the current
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371 | C<LC_NUMERIC> and C<LC_MONETARY> locales. (If you just want the name of
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372 | the current locale for a particular category, use POSIX::setlocale()
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373 | with a single parameter--see L<The setlocale function>.)
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374 |
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375 | use POSIX qw(locale_h);
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376 |
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377 | # Get a reference to a hash of locale-dependent info
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378 | $locale_values = localeconv();
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379 |
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380 | # Output sorted list of the values
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381 | for (sort keys %$locale_values) {
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382 | printf "%-20s = %s\n", $_, $locale_values->{$_}
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383 | }
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384 |
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385 | localeconv() takes no arguments, and returns B<a reference to> a hash.
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386 | The keys of this hash are variable names for formatting, such as
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387 | C<decimal_point> and C<thousands_sep>. The values are the
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388 | corresponding, er, values. See L<POSIX/localeconv> for a longer
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389 | example listing the categories an implementation might be expected to
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390 | provide; some provide more and others fewer. You don't need an
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391 | explicit C<use locale>, because localeconv() always observes the
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392 | current locale.
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393 |
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394 | Here's a simple-minded example program that rewrites its command-line
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395 | parameters as integers correctly formatted in the current locale:
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396 |
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397 | # See comments in previous example
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398 | require 5.004;
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399 | use POSIX qw(locale_h);
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400 |
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401 | # Get some of locale's numeric formatting parameters
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402 | my ($thousands_sep, $grouping) =
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403 | @{localeconv()}{'thousands_sep', 'grouping'};
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404 |
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405 | # Apply defaults if values are missing
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406 | $thousands_sep = ',' unless $thousands_sep;
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407 |
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408 | # grouping and mon_grouping are packed lists
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409 | # of small integers (characters) telling the
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410 | # grouping (thousand_seps and mon_thousand_seps
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411 | # being the group dividers) of numbers and
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412 | # monetary quantities. The integers' meanings:
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413 | # 255 means no more grouping, 0 means repeat
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414 | # the previous grouping, 1-254 means use that
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415 | # as the current grouping. Grouping goes from
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416 | # right to left (low to high digits). In the
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417 | # below we cheat slightly by never using anything
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418 | # else than the first grouping (whatever that is).
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419 | if ($grouping) {
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420 | @grouping = unpack("C*", $grouping);
|
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421 | } else {
|
---|
422 | @grouping = (3);
|
---|
423 | }
|
---|
424 |
|
---|
425 | # Format command line params for current locale
|
---|
426 | for (@ARGV) {
|
---|
427 | $_ = int; # Chop non-integer part
|
---|
428 | 1 while
|
---|
429 | s/(\d)(\d{$grouping[0]}($|$thousands_sep))/$1$thousands_sep$2/;
|
---|
430 | print "$_";
|
---|
431 | }
|
---|
432 | print "\n";
|
---|
433 |
|
---|
434 | =head2 I18N::Langinfo
|
---|
435 |
|
---|
436 | Another interface for querying locale-dependent information is the
|
---|
437 | I18N::Langinfo::langinfo() function, available at least in UNIX-like
|
---|
438 | systems and VMS.
|
---|
439 |
|
---|
440 | The following example will import the langinfo() function itself and
|
---|
441 | three constants to be used as arguments to langinfo(): a constant for
|
---|
442 | the abbreviated first day of the week (the numbering starts from
|
---|
443 | Sunday = 1) and two more constants for the affirmative and negative
|
---|
444 | answers for a yes/no question in the current locale.
|
---|
445 |
|
---|
446 | use I18N::Langinfo qw(langinfo ABDAY_1 YESSTR NOSTR);
|
---|
447 |
|
---|
448 | my ($abday_1, $yesstr, $nostr) = map { langinfo } qw(ABDAY_1 YESSTR NOSTR);
|
---|
449 |
|
---|
450 | print "$abday_1? [$yesstr/$nostr] ";
|
---|
451 |
|
---|
452 | In other words, in the "C" (or English) locale the above will probably
|
---|
453 | print something like:
|
---|
454 |
|
---|
455 | Sun? [yes/no]
|
---|
456 |
|
---|
457 | See L<I18N::Langinfo> for more information.
|
---|
458 |
|
---|
459 | =head1 LOCALE CATEGORIES
|
---|
460 |
|
---|
461 | The following subsections describe basic locale categories. Beyond these,
|
---|
462 | some combination categories allow manipulation of more than one
|
---|
463 | basic category at a time. See L<"ENVIRONMENT"> for a discussion of these.
|
---|
464 |
|
---|
465 | =head2 Category LC_COLLATE: Collation
|
---|
466 |
|
---|
467 | In the scope of S<C<use locale>>, Perl looks to the C<LC_COLLATE>
|
---|
468 | environment variable to determine the application's notions on collation
|
---|
469 | (ordering) of characters. For example, 'b' follows 'a' in Latin
|
---|
470 | alphabets, but where do 'E<aacute>' and 'E<aring>' belong? And while
|
---|
471 | 'color' follows 'chocolate' in English, what about in Spanish?
|
---|
472 |
|
---|
473 | The following collations all make sense and you may meet any of them
|
---|
474 | if you "use locale".
|
---|
475 |
|
---|
476 | A B C D E a b c d e
|
---|
477 | A a B b C c D d E e
|
---|
478 | a A b B c C d D e E
|
---|
479 | a b c d e A B C D E
|
---|
480 |
|
---|
481 | Here is a code snippet to tell what "word"
|
---|
482 | characters are in the current locale, in that locale's order:
|
---|
483 |
|
---|
484 | use locale;
|
---|
485 | print +(sort grep /\w/, map { chr } 0..255), "\n";
|
---|
486 |
|
---|
487 | Compare this with the characters that you see and their order if you
|
---|
488 | state explicitly that the locale should be ignored:
|
---|
489 |
|
---|
490 | no locale;
|
---|
491 | print +(sort grep /\w/, map { chr } 0..255), "\n";
|
---|
492 |
|
---|
493 | This machine-native collation (which is what you get unless S<C<use
|
---|
494 | locale>> has appeared earlier in the same block) must be used for
|
---|
495 | sorting raw binary data, whereas the locale-dependent collation of the
|
---|
496 | first example is useful for natural text.
|
---|
497 |
|
---|
498 | As noted in L<USING LOCALES>, C<cmp> compares according to the current
|
---|
499 | collation locale when C<use locale> is in effect, but falls back to a
|
---|
500 | char-by-char comparison for strings that the locale says are equal. You
|
---|
501 | can use POSIX::strcoll() if you don't want this fall-back:
|
---|
502 |
|
---|
503 | use POSIX qw(strcoll);
|
---|
504 | $equal_in_locale =
|
---|
505 | !strcoll("space and case ignored", "SpaceAndCaseIgnored");
|
---|
506 |
|
---|
507 | $equal_in_locale will be true if the collation locale specifies a
|
---|
508 | dictionary-like ordering that ignores space characters completely and
|
---|
509 | which folds case.
|
---|
510 |
|
---|
511 | If you have a single string that you want to check for "equality in
|
---|
512 | locale" against several others, you might think you could gain a little
|
---|
513 | efficiency by using POSIX::strxfrm() in conjunction with C<eq>:
|
---|
514 |
|
---|
515 | use POSIX qw(strxfrm);
|
---|
516 | $xfrm_string = strxfrm("Mixed-case string");
|
---|
517 | print "locale collation ignores spaces\n"
|
---|
518 | if $xfrm_string eq strxfrm("Mixed-casestring");
|
---|
519 | print "locale collation ignores hyphens\n"
|
---|
520 | if $xfrm_string eq strxfrm("Mixedcase string");
|
---|
521 | print "locale collation ignores case\n"
|
---|
522 | if $xfrm_string eq strxfrm("mixed-case string");
|
---|
523 |
|
---|
524 | strxfrm() takes a string and maps it into a transformed string for use
|
---|
525 | in char-by-char comparisons against other transformed strings during
|
---|
526 | collation. "Under the hood", locale-affected Perl comparison operators
|
---|
527 | call strxfrm() for both operands, then do a char-by-char
|
---|
528 | comparison of the transformed strings. By calling strxfrm() explicitly
|
---|
529 | and using a non locale-affected comparison, the example attempts to save
|
---|
530 | a couple of transformations. But in fact, it doesn't save anything: Perl
|
---|
531 | magic (see L<perlguts/Magic Variables>) creates the transformed version of a
|
---|
532 | string the first time it's needed in a comparison, then keeps this version around
|
---|
533 | in case it's needed again. An example rewritten the easy way with
|
---|
534 | C<cmp> runs just about as fast. It also copes with null characters
|
---|
535 | embedded in strings; if you call strxfrm() directly, it treats the first
|
---|
536 | null it finds as a terminator. don't expect the transformed strings
|
---|
537 | it produces to be portable across systems--or even from one revision
|
---|
538 | of your operating system to the next. In short, don't call strxfrm()
|
---|
539 | directly: let Perl do it for you.
|
---|
540 |
|
---|
541 | Note: C<use locale> isn't shown in some of these examples because it isn't
|
---|
542 | needed: strcoll() and strxfrm() exist only to generate locale-dependent
|
---|
543 | results, and so always obey the current C<LC_COLLATE> locale.
|
---|
544 |
|
---|
545 | =head2 Category LC_CTYPE: Character Types
|
---|
546 |
|
---|
547 | In the scope of S<C<use locale>>, Perl obeys the C<LC_CTYPE> locale
|
---|
548 | setting. This controls the application's notion of which characters are
|
---|
549 | alphabetic. This affects Perl's C<\w> regular expression metanotation,
|
---|
550 | which stands for alphanumeric characters--that is, alphabetic,
|
---|
551 | numeric, and including other special characters such as the underscore or
|
---|
552 | hyphen. (Consult L<perlre> for more information about
|
---|
553 | regular expressions.) Thanks to C<LC_CTYPE>, depending on your locale
|
---|
554 | setting, characters like 'E<aelig>', 'E<eth>', 'E<szlig>', and
|
---|
555 | 'E<oslash>' may be understood as C<\w> characters.
|
---|
556 |
|
---|
557 | The C<LC_CTYPE> locale also provides the map used in transliterating
|
---|
558 | characters between lower and uppercase. This affects the case-mapping
|
---|
559 | functions--lc(), lcfirst, uc(), and ucfirst(); case-mapping
|
---|
560 | interpolation with C<\l>, C<\L>, C<\u>, or C<\U> in double-quoted strings
|
---|
561 | and C<s///> substitutions; and case-independent regular expression
|
---|
562 | pattern matching using the C<i> modifier.
|
---|
563 |
|
---|
564 | Finally, C<LC_CTYPE> affects the POSIX character-class test
|
---|
565 | functions--isalpha(), islower(), and so on. For example, if you move
|
---|
566 | from the "C" locale to a 7-bit Scandinavian one, you may find--possibly
|
---|
567 | to your surprise--that "|" moves from the ispunct() class to isalpha().
|
---|
568 |
|
---|
569 | B<Note:> A broken or malicious C<LC_CTYPE> locale definition may result
|
---|
570 | in clearly ineligible characters being considered to be alphanumeric by
|
---|
571 | your application. For strict matching of (mundane) letters and
|
---|
572 | digits--for example, in command strings--locale-aware applications
|
---|
573 | should use C<\w> inside a C<no locale> block. See L<"SECURITY">.
|
---|
574 |
|
---|
575 | =head2 Category LC_NUMERIC: Numeric Formatting
|
---|
576 |
|
---|
577 | In the scope of S<C<use locale>>, Perl obeys the C<LC_NUMERIC> locale
|
---|
578 | information, which controls an application's idea of how numbers should
|
---|
579 | be formatted for human readability by the printf(), sprintf(), and
|
---|
580 | write() functions. String-to-numeric conversion by the POSIX::strtod()
|
---|
581 | function is also affected. In most implementations the only effect is to
|
---|
582 | change the character used for the decimal point--perhaps from '.' to ','.
|
---|
583 | These functions aren't aware of such niceties as thousands separation and
|
---|
584 | so on. (See L<The localeconv function> if you care about these things.)
|
---|
585 |
|
---|
586 | Output produced by print() is also affected by the current locale: it
|
---|
587 | depends on whether C<use locale> or C<no locale> is in effect, and
|
---|
588 | corresponds to what you'd get from printf() in the "C" locale. The
|
---|
589 | same is true for Perl's internal conversions between numeric and
|
---|
590 | string formats:
|
---|
591 |
|
---|
592 | use POSIX qw(strtod);
|
---|
593 | use locale;
|
---|
594 |
|
---|
595 | $n = 5/2; # Assign numeric 2.5 to $n
|
---|
596 |
|
---|
597 | $a = " $n"; # Locale-dependent conversion to string
|
---|
598 |
|
---|
599 | print "half five is $n\n"; # Locale-dependent output
|
---|
600 |
|
---|
601 | printf "half five is %g\n", $n; # Locale-dependent output
|
---|
602 |
|
---|
603 | print "DECIMAL POINT IS COMMA\n"
|
---|
604 | if $n == (strtod("2,5"))[0]; # Locale-dependent conversion
|
---|
605 |
|
---|
606 | See also L<I18N::Langinfo> and C<RADIXCHAR>.
|
---|
607 |
|
---|
608 | =head2 Category LC_MONETARY: Formatting of monetary amounts
|
---|
609 |
|
---|
610 | The C standard defines the C<LC_MONETARY> category, but no function
|
---|
611 | that is affected by its contents. (Those with experience of standards
|
---|
612 | committees will recognize that the working group decided to punt on the
|
---|
613 | issue.) Consequently, Perl takes no notice of it. If you really want
|
---|
614 | to use C<LC_MONETARY>, you can query its contents--see
|
---|
615 | L<The localeconv function>--and use the information that it returns in your
|
---|
616 | application's own formatting of currency amounts. However, you may well
|
---|
617 | find that the information, voluminous and complex though it may be, still
|
---|
618 | does not quite meet your requirements: currency formatting is a hard nut
|
---|
619 | to crack.
|
---|
620 |
|
---|
621 | See also L<I18N::Langinfo> and C<CRNCYSTR>.
|
---|
622 |
|
---|
623 | =head2 LC_TIME
|
---|
624 |
|
---|
625 | Output produced by POSIX::strftime(), which builds a formatted
|
---|
626 | human-readable date/time string, is affected by the current C<LC_TIME>
|
---|
627 | locale. Thus, in a French locale, the output produced by the C<%B>
|
---|
628 | format element (full month name) for the first month of the year would
|
---|
629 | be "janvier". Here's how to get a list of long month names in the
|
---|
630 | current locale:
|
---|
631 |
|
---|
632 | use POSIX qw(strftime);
|
---|
633 | for (0..11) {
|
---|
634 | $long_month_name[$_] =
|
---|
635 | strftime("%B", 0, 0, 0, 1, $_, 96);
|
---|
636 | }
|
---|
637 |
|
---|
638 | Note: C<use locale> isn't needed in this example: as a function that
|
---|
639 | exists only to generate locale-dependent results, strftime() always
|
---|
640 | obeys the current C<LC_TIME> locale.
|
---|
641 |
|
---|
642 | See also L<I18N::Langinfo> and C<ABDAY_1>..C<ABDAY_7>, C<DAY_1>..C<DAY_7>,
|
---|
643 | C<ABMON_1>..C<ABMON_12>, and C<ABMON_1>..C<ABMON_12>.
|
---|
644 |
|
---|
645 | =head2 Other categories
|
---|
646 |
|
---|
647 | The remaining locale category, C<LC_MESSAGES> (possibly supplemented
|
---|
648 | by others in particular implementations) is not currently used by
|
---|
649 | Perl--except possibly to affect the behavior of library functions
|
---|
650 | called by extensions outside the standard Perl distribution and by the
|
---|
651 | operating system and its utilities. Note especially that the string
|
---|
652 | value of C<$!> and the error messages given by external utilities may
|
---|
653 | be changed by C<LC_MESSAGES>. If you want to have portable error
|
---|
654 | codes, use C<%!>. See L<Errno>.
|
---|
655 |
|
---|
656 | =head1 SECURITY
|
---|
657 |
|
---|
658 | Although the main discussion of Perl security issues can be found in
|
---|
659 | L<perlsec>, a discussion of Perl's locale handling would be incomplete
|
---|
660 | if it did not draw your attention to locale-dependent security issues.
|
---|
661 | Locales--particularly on systems that allow unprivileged users to
|
---|
662 | build their own locales--are untrustworthy. A malicious (or just plain
|
---|
663 | broken) locale can make a locale-aware application give unexpected
|
---|
664 | results. Here are a few possibilities:
|
---|
665 |
|
---|
666 | =over 4
|
---|
667 |
|
---|
668 | =item *
|
---|
669 |
|
---|
670 | Regular expression checks for safe file names or mail addresses using
|
---|
671 | C<\w> may be spoofed by an C<LC_CTYPE> locale that claims that
|
---|
672 | characters such as "E<gt>" and "|" are alphanumeric.
|
---|
673 |
|
---|
674 | =item *
|
---|
675 |
|
---|
676 | String interpolation with case-mapping, as in, say, C<$dest =
|
---|
677 | "C:\U$name.$ext">, may produce dangerous results if a bogus LC_CTYPE
|
---|
678 | case-mapping table is in effect.
|
---|
679 |
|
---|
680 | =item *
|
---|
681 |
|
---|
682 | A sneaky C<LC_COLLATE> locale could result in the names of students with
|
---|
683 | "D" grades appearing ahead of those with "A"s.
|
---|
684 |
|
---|
685 | =item *
|
---|
686 |
|
---|
687 | An application that takes the trouble to use information in
|
---|
688 | C<LC_MONETARY> may format debits as if they were credits and vice versa
|
---|
689 | if that locale has been subverted. Or it might make payments in US
|
---|
690 | dollars instead of Hong Kong dollars.
|
---|
691 |
|
---|
692 | =item *
|
---|
693 |
|
---|
694 | The date and day names in dates formatted by strftime() could be
|
---|
695 | manipulated to advantage by a malicious user able to subvert the
|
---|
696 | C<LC_DATE> locale. ("Look--it says I wasn't in the building on
|
---|
697 | Sunday.")
|
---|
698 |
|
---|
699 | =back
|
---|
700 |
|
---|
701 | Such dangers are not peculiar to the locale system: any aspect of an
|
---|
702 | application's environment which may be modified maliciously presents
|
---|
703 | similar challenges. Similarly, they are not specific to Perl: any
|
---|
704 | programming language that allows you to write programs that take
|
---|
705 | account of their environment exposes you to these issues.
|
---|
706 |
|
---|
707 | Perl cannot protect you from all possibilities shown in the
|
---|
708 | examples--there is no substitute for your own vigilance--but, when
|
---|
709 | C<use locale> is in effect, Perl uses the tainting mechanism (see
|
---|
710 | L<perlsec>) to mark string results that become locale-dependent, and
|
---|
711 | which may be untrustworthy in consequence. Here is a summary of the
|
---|
712 | tainting behavior of operators and functions that may be affected by
|
---|
713 | the locale:
|
---|
714 |
|
---|
715 | =over 4
|
---|
716 |
|
---|
717 | =item *
|
---|
718 |
|
---|
719 | B<Comparison operators> (C<lt>, C<le>, C<ge>, C<gt> and C<cmp>):
|
---|
720 |
|
---|
721 | Scalar true/false (or less/equal/greater) result is never tainted.
|
---|
722 |
|
---|
723 | =item *
|
---|
724 |
|
---|
725 | B<Case-mapping interpolation> (with C<\l>, C<\L>, C<\u> or C<\U>)
|
---|
726 |
|
---|
727 | Result string containing interpolated material is tainted if
|
---|
728 | C<use locale> is in effect.
|
---|
729 |
|
---|
730 | =item *
|
---|
731 |
|
---|
732 | B<Matching operator> (C<m//>):
|
---|
733 |
|
---|
734 | Scalar true/false result never tainted.
|
---|
735 |
|
---|
736 | Subpatterns, either delivered as a list-context result or as $1 etc.
|
---|
737 | are tainted if C<use locale> is in effect, and the subpattern regular
|
---|
738 | expression contains C<\w> (to match an alphanumeric character), C<\W>
|
---|
739 | (non-alphanumeric character), C<\s> (whitespace character), or C<\S>
|
---|
740 | (non whitespace character). The matched-pattern variable, $&, $`
|
---|
741 | (pre-match), $' (post-match), and $+ (last match) are also tainted if
|
---|
742 | C<use locale> is in effect and the regular expression contains C<\w>,
|
---|
743 | C<\W>, C<\s>, or C<\S>.
|
---|
744 |
|
---|
745 | =item *
|
---|
746 |
|
---|
747 | B<Substitution operator> (C<s///>):
|
---|
748 |
|
---|
749 | Has the same behavior as the match operator. Also, the left
|
---|
750 | operand of C<=~> becomes tainted when C<use locale> in effect
|
---|
751 | if modified as a result of a substitution based on a regular
|
---|
752 | expression match involving C<\w>, C<\W>, C<\s>, or C<\S>; or of
|
---|
753 | case-mapping with C<\l>, C<\L>,C<\u> or C<\U>.
|
---|
754 |
|
---|
755 | =item *
|
---|
756 |
|
---|
757 | B<Output formatting functions> (printf() and write()):
|
---|
758 |
|
---|
759 | Results are never tainted because otherwise even output from print,
|
---|
760 | for example C<print(1/7)>, should be tainted if C<use locale> is in
|
---|
761 | effect.
|
---|
762 |
|
---|
763 | =item *
|
---|
764 |
|
---|
765 | B<Case-mapping functions> (lc(), lcfirst(), uc(), ucfirst()):
|
---|
766 |
|
---|
767 | Results are tainted if C<use locale> is in effect.
|
---|
768 |
|
---|
769 | =item *
|
---|
770 |
|
---|
771 | B<POSIX locale-dependent functions> (localeconv(), strcoll(),
|
---|
772 | strftime(), strxfrm()):
|
---|
773 |
|
---|
774 | Results are never tainted.
|
---|
775 |
|
---|
776 | =item *
|
---|
777 |
|
---|
778 | B<POSIX character class tests> (isalnum(), isalpha(), isdigit(),
|
---|
779 | isgraph(), islower(), isprint(), ispunct(), isspace(), isupper(),
|
---|
780 | isxdigit()):
|
---|
781 |
|
---|
782 | True/false results are never tainted.
|
---|
783 |
|
---|
784 | =back
|
---|
785 |
|
---|
786 | Three examples illustrate locale-dependent tainting.
|
---|
787 | The first program, which ignores its locale, won't run: a value taken
|
---|
788 | directly from the command line may not be used to name an output file
|
---|
789 | when taint checks are enabled.
|
---|
790 |
|
---|
791 | #/usr/local/bin/perl -T
|
---|
792 | # Run with taint checking
|
---|
793 |
|
---|
794 | # Command line sanity check omitted...
|
---|
795 | $tainted_output_file = shift;
|
---|
796 |
|
---|
797 | open(F, ">$tainted_output_file")
|
---|
798 | or warn "Open of $untainted_output_file failed: $!\n";
|
---|
799 |
|
---|
800 | The program can be made to run by "laundering" the tainted value through
|
---|
801 | a regular expression: the second example--which still ignores locale
|
---|
802 | information--runs, creating the file named on its command line
|
---|
803 | if it can.
|
---|
804 |
|
---|
805 | #/usr/local/bin/perl -T
|
---|
806 |
|
---|
807 | $tainted_output_file = shift;
|
---|
808 | $tainted_output_file =~ m%[\w/]+%;
|
---|
809 | $untainted_output_file = $&;
|
---|
810 |
|
---|
811 | open(F, ">$untainted_output_file")
|
---|
812 | or warn "Open of $untainted_output_file failed: $!\n";
|
---|
813 |
|
---|
814 | Compare this with a similar but locale-aware program:
|
---|
815 |
|
---|
816 | #/usr/local/bin/perl -T
|
---|
817 |
|
---|
818 | $tainted_output_file = shift;
|
---|
819 | use locale;
|
---|
820 | $tainted_output_file =~ m%[\w/]+%;
|
---|
821 | $localized_output_file = $&;
|
---|
822 |
|
---|
823 | open(F, ">$localized_output_file")
|
---|
824 | or warn "Open of $localized_output_file failed: $!\n";
|
---|
825 |
|
---|
826 | This third program fails to run because $& is tainted: it is the result
|
---|
827 | of a match involving C<\w> while C<use locale> is in effect.
|
---|
828 |
|
---|
829 | =head1 ENVIRONMENT
|
---|
830 |
|
---|
831 | =over 12
|
---|
832 |
|
---|
833 | =item PERL_BADLANG
|
---|
834 |
|
---|
835 | A string that can suppress Perl's warning about failed locale settings
|
---|
836 | at startup. Failure can occur if the locale support in the operating
|
---|
837 | system is lacking (broken) in some way--or if you mistyped the name of
|
---|
838 | a locale when you set up your environment. If this environment
|
---|
839 | variable is absent, or has a value that does not evaluate to integer
|
---|
840 | zero--that is, "0" or ""-- Perl will complain about locale setting
|
---|
841 | failures.
|
---|
842 |
|
---|
843 | B<NOTE>: PERL_BADLANG only gives you a way to hide the warning message.
|
---|
844 | The message tells about some problem in your system's locale support,
|
---|
845 | and you should investigate what the problem is.
|
---|
846 |
|
---|
847 | =back
|
---|
848 |
|
---|
849 | The following environment variables are not specific to Perl: They are
|
---|
850 | part of the standardized (ISO C, XPG4, POSIX 1.c) setlocale() method
|
---|
851 | for controlling an application's opinion on data.
|
---|
852 |
|
---|
853 | =over 12
|
---|
854 |
|
---|
855 | =item LC_ALL
|
---|
856 |
|
---|
857 | C<LC_ALL> is the "override-all" locale environment variable. If
|
---|
858 | set, it overrides all the rest of the locale environment variables.
|
---|
859 |
|
---|
860 | =item LANGUAGE
|
---|
861 |
|
---|
862 | B<NOTE>: C<LANGUAGE> is a GNU extension, it affects you only if you
|
---|
863 | are using the GNU libc. This is the case if you are using e.g. Linux.
|
---|
864 | If you are using "commercial" UNIXes you are most probably I<not>
|
---|
865 | using GNU libc and you can ignore C<LANGUAGE>.
|
---|
866 |
|
---|
867 | However, in the case you are using C<LANGUAGE>: it affects the
|
---|
868 | language of informational, warning, and error messages output by
|
---|
869 | commands (in other words, it's like C<LC_MESSAGES>) but it has higher
|
---|
870 | priority than L<LC_ALL>. Moreover, it's not a single value but
|
---|
871 | instead a "path" (":"-separated list) of I<languages> (not locales).
|
---|
872 | See the GNU C<gettext> library documentation for more information.
|
---|
873 |
|
---|
874 | =item LC_CTYPE
|
---|
875 |
|
---|
876 | In the absence of C<LC_ALL>, C<LC_CTYPE> chooses the character type
|
---|
877 | locale. In the absence of both C<LC_ALL> and C<LC_CTYPE>, C<LANG>
|
---|
878 | chooses the character type locale.
|
---|
879 |
|
---|
880 | =item LC_COLLATE
|
---|
881 |
|
---|
882 | In the absence of C<LC_ALL>, C<LC_COLLATE> chooses the collation
|
---|
883 | (sorting) locale. In the absence of both C<LC_ALL> and C<LC_COLLATE>,
|
---|
884 | C<LANG> chooses the collation locale.
|
---|
885 |
|
---|
886 | =item LC_MONETARY
|
---|
887 |
|
---|
888 | In the absence of C<LC_ALL>, C<LC_MONETARY> chooses the monetary
|
---|
889 | formatting locale. In the absence of both C<LC_ALL> and C<LC_MONETARY>,
|
---|
890 | C<LANG> chooses the monetary formatting locale.
|
---|
891 |
|
---|
892 | =item LC_NUMERIC
|
---|
893 |
|
---|
894 | In the absence of C<LC_ALL>, C<LC_NUMERIC> chooses the numeric format
|
---|
895 | locale. In the absence of both C<LC_ALL> and C<LC_NUMERIC>, C<LANG>
|
---|
896 | chooses the numeric format.
|
---|
897 |
|
---|
898 | =item LC_TIME
|
---|
899 |
|
---|
900 | In the absence of C<LC_ALL>, C<LC_TIME> chooses the date and time
|
---|
901 | formatting locale. In the absence of both C<LC_ALL> and C<LC_TIME>,
|
---|
902 | C<LANG> chooses the date and time formatting locale.
|
---|
903 |
|
---|
904 | =item LANG
|
---|
905 |
|
---|
906 | C<LANG> is the "catch-all" locale environment variable. If it is set, it
|
---|
907 | is used as the last resort after the overall C<LC_ALL> and the
|
---|
908 | category-specific C<LC_...>.
|
---|
909 |
|
---|
910 | =back
|
---|
911 |
|
---|
912 | =head1 NOTES
|
---|
913 |
|
---|
914 | =head2 Backward compatibility
|
---|
915 |
|
---|
916 | Versions of Perl prior to 5.004 B<mostly> ignored locale information,
|
---|
917 | generally behaving as if something similar to the C<"C"> locale were
|
---|
918 | always in force, even if the program environment suggested otherwise
|
---|
919 | (see L<The setlocale function>). By default, Perl still behaves this
|
---|
920 | way for backward compatibility. If you want a Perl application to pay
|
---|
921 | attention to locale information, you B<must> use the S<C<use locale>>
|
---|
922 | pragma (see L<The use locale pragma>) to instruct it to do so.
|
---|
923 |
|
---|
924 | Versions of Perl from 5.002 to 5.003 did use the C<LC_CTYPE>
|
---|
925 | information if available; that is, C<\w> did understand what
|
---|
926 | were the letters according to the locale environment variables.
|
---|
927 | The problem was that the user had no control over the feature:
|
---|
928 | if the C library supported locales, Perl used them.
|
---|
929 |
|
---|
930 | =head2 I18N:Collate obsolete
|
---|
931 |
|
---|
932 | In versions of Perl prior to 5.004, per-locale collation was possible
|
---|
933 | using the C<I18N::Collate> library module. This module is now mildly
|
---|
934 | obsolete and should be avoided in new applications. The C<LC_COLLATE>
|
---|
935 | functionality is now integrated into the Perl core language: One can
|
---|
936 | use locale-specific scalar data completely normally with C<use locale>,
|
---|
937 | so there is no longer any need to juggle with the scalar references of
|
---|
938 | C<I18N::Collate>.
|
---|
939 |
|
---|
940 | =head2 Sort speed and memory use impacts
|
---|
941 |
|
---|
942 | Comparing and sorting by locale is usually slower than the default
|
---|
943 | sorting; slow-downs of two to four times have been observed. It will
|
---|
944 | also consume more memory: once a Perl scalar variable has participated
|
---|
945 | in any string comparison or sorting operation obeying the locale
|
---|
946 | collation rules, it will take 3-15 times more memory than before. (The
|
---|
947 | exact multiplier depends on the string's contents, the operating system
|
---|
948 | and the locale.) These downsides are dictated more by the operating
|
---|
949 | system's implementation of the locale system than by Perl.
|
---|
950 |
|
---|
951 | =head2 write() and LC_NUMERIC
|
---|
952 |
|
---|
953 | Formats are the only part of Perl that unconditionally use information
|
---|
954 | from a program's locale; if a program's environment specifies an
|
---|
955 | LC_NUMERIC locale, it is always used to specify the decimal point
|
---|
956 | character in formatted output. Formatted output cannot be controlled by
|
---|
957 | C<use locale> because the pragma is tied to the block structure of the
|
---|
958 | program, and, for historical reasons, formats exist outside that block
|
---|
959 | structure.
|
---|
960 |
|
---|
961 | =head2 Freely available locale definitions
|
---|
962 |
|
---|
963 | There is a large collection of locale definitions at
|
---|
964 | ftp://dkuug.dk/i18n/WG15-collection . You should be aware that it is
|
---|
965 | unsupported, and is not claimed to be fit for any purpose. If your
|
---|
966 | system allows installation of arbitrary locales, you may find the
|
---|
967 | definitions useful as they are, or as a basis for the development of
|
---|
968 | your own locales.
|
---|
969 |
|
---|
970 | =head2 I18n and l10n
|
---|
971 |
|
---|
972 | "Internationalization" is often abbreviated as B<i18n> because its first
|
---|
973 | and last letters are separated by eighteen others. (You may guess why
|
---|
974 | the internalin ... internaliti ... i18n tends to get abbreviated.) In
|
---|
975 | the same way, "localization" is often abbreviated to B<l10n>.
|
---|
976 |
|
---|
977 | =head2 An imperfect standard
|
---|
978 |
|
---|
979 | Internationalization, as defined in the C and POSIX standards, can be
|
---|
980 | criticized as incomplete, ungainly, and having too large a granularity.
|
---|
981 | (Locales apply to a whole process, when it would arguably be more useful
|
---|
982 | to have them apply to a single thread, window group, or whatever.) They
|
---|
983 | also have a tendency, like standards groups, to divide the world into
|
---|
984 | nations, when we all know that the world can equally well be divided
|
---|
985 | into bankers, bikers, gamers, and so on. But, for now, it's the only
|
---|
986 | standard we've got. This may be construed as a bug.
|
---|
987 |
|
---|
988 | =head1 Unicode and UTF-8
|
---|
989 |
|
---|
990 | The support of Unicode is new starting from Perl version 5.6, and
|
---|
991 | more fully implemented in the version 5.8. See L<perluniintro> and
|
---|
992 | L<perlunicode> for more details.
|
---|
993 |
|
---|
994 | Usually locale settings and Unicode do not affect each other, but
|
---|
995 | there are exceptions, see L<perlunicode/Locales> for examples.
|
---|
996 |
|
---|
997 | =head1 BUGS
|
---|
998 |
|
---|
999 | =head2 Broken systems
|
---|
1000 |
|
---|
1001 | In certain systems, the operating system's locale support
|
---|
1002 | is broken and cannot be fixed or used by Perl. Such deficiencies can
|
---|
1003 | and will result in mysterious hangs and/or Perl core dumps when the
|
---|
1004 | C<use locale> is in effect. When confronted with such a system,
|
---|
1005 | please report in excruciating detail to <F<[email protected]>>, and
|
---|
1006 | complain to your vendor: bug fixes may exist for these problems
|
---|
1007 | in your operating system. Sometimes such bug fixes are called an
|
---|
1008 | operating system upgrade.
|
---|
1009 |
|
---|
1010 | =head1 SEE ALSO
|
---|
1011 |
|
---|
1012 | L<I18N::Langinfo>, L<perluniintro>, L<perlunicode>, L<open>,
|
---|
1013 | L<POSIX/isalnum>, L<POSIX/isalpha>,
|
---|
1014 | L<POSIX/isdigit>, L<POSIX/isgraph>, L<POSIX/islower>,
|
---|
1015 | L<POSIX/isprint>, L<POSIX/ispunct>, L<POSIX/isspace>,
|
---|
1016 | L<POSIX/isupper>, L<POSIX/isxdigit>, L<POSIX/localeconv>,
|
---|
1017 | L<POSIX/setlocale>, L<POSIX/strcoll>, L<POSIX/strftime>,
|
---|
1018 | L<POSIX/strtod>, L<POSIX/strxfrm>.
|
---|
1019 |
|
---|
1020 | =head1 HISTORY
|
---|
1021 |
|
---|
1022 | Jarkko Hietaniemi's original F<perli18n.pod> heavily hacked by Dominic
|
---|
1023 | Dunlop, assisted by the perl5-porters. Prose worked over a bit by
|
---|
1024 | Tom Christiansen.
|
---|
1025 |
|
---|
1026 | Last update: Thu Jun 11 08:44:13 MDT 1998
|
---|